Does endurance training affect orthostatic responses in healthy elderly men?

Area of Science:

• Exercise Physiology
• Gerontology
• Cardiovascular Regulation

Background:

• Aging is associated with declines in cardiorespiratory fitness and potential alterations in cardiovascular regulation.
• Endurance training is a common intervention to improve cardiorespiratory fitness across the lifespan.

Purpose of the Study:

• To investigate the effects of endurance training on cardiovascular and neurohormonal responses during orthostatic stress in healthy elderly men.
• To determine the time course of these adaptations over a 12-week training period.

Main Methods:

• Healthy elderly men (65-75 years) were randomized into endurance training (EX) or control (CON) groups.
• The EX group underwent 12 weeks of cycling exercise (3x/week, 30 min, 70% VO2peak).
• Orthostatic stress was assessed using 90-degree head-up tilt, measuring heart rate, arterial pressure, norepinephrine, and plasma volume.

Main Results:

• Endurance training significantly increased VO2peak by 10% in the EX group.
• No significant differences were observed between groups in heart rate, arterial pressure, or plasma volume regulation during head-up tilt.
• Norepinephrine responses during orthostatic stress also remained similar between the endurance-trained and control groups.

Conclusions:

• Endurance training can improve cardiorespiratory fitness in healthy elderly men.
• These improvements can be achieved without compromising the regulation of heart rate, arterial pressure, or plasma volume during orthostatic challenges.
• The findings suggest that endurance exercise is safe and effective for enhancing fitness in older adults without adverse effects on autonomic cardiovascular control.